(a) Consider the differential equation $$x\frac{dy}{dx} - 2 y = 0.$$
Find a general solution to this differential equation that has the form $y = Cx^n$.
$y =$ .
Find a second solution $y = Cx^n$ that might not be a general solution and which may have a different value of $n$ than your first solution.
$y =$ .

(b) If the solution additionally satisfies $y=15$ when $x=4$, what is the solution?
$y =$